Rear oil seal for journal boxes



Jan. 7, 1964 C, s, B01-MER 3,116,933

REAR OIL SEAL FOR JOURNAL BOXES Filed Aug. 4, 1959 IN V EN TOR.

United States Patent() 3,116,933 REAR @EL FR JOURNAL BXES Chai-ies S.Ballmer, Hillsboro, Ill., assignor to` Railway Car Equipmentv Co.,Hillsboro, Ill., a corporation of Illinois Filed Aug. 4, 1959,53. No.831,653 2 Claims. (Cl. 277-174) This invention relates generally torailroad car journal boxes and concerns more particularly a rear oilseal for use in such boxes.

Journal boxes of the type commonly used for supporting a railroad cai onits axles are conventionally provided with a sealing device adapted tosnugly surround the axle dry seat, or fillet portion, at the point wherethe axle enters the journal box. VThe sealing device thus seals oli theopening ythrough which the axle enters the journal box, preventing dustand other foreign material from entering the box while retaininglubricant therein for lubricating the supporting Deming or brass.Conventional journal boxes have a vertical slot or groove at the pointwhere the axle enters the box, called the dust guard well, which isadapted to receive and retain a rear oil seal in proper position.

Seals of this type are subject to very hard usage during normaloperation since the axle journal of a railroad car does not remainexactly centered with respect to the journal box when the car isrunning. Indeed, an axle journal and journal box may shift relative toone another a distance oi over ll/z inches when the cars brakes areapplied or the car is otherwise jolted, and it has been observed thatthe journal brass will jump up to 3A of an inch above the axle journalwhen track imperfections are encountered at high speeds. Thus,y not onlyis the axle rotating quite rapidly within the rear oil seal, but theaxle will also be frequently jarred laterally and down into the body ofthe seal. Y

It is therefore an object of the invention to providea rear oil seal forstandard journal box assemblies which readily accommodates relativeaxle-journal boximovernent while minimizing the likelihood of the sealbeing unseated from the dry seat or fillet portion of the axle journal.

It is an equally important and related object to provide a seal ascharacterized above that, inthe event the seal is separated from theaxle dry seat, permits the parts to regain their normal sealingrelationship without crushing or jamming the seal against the rough castwall surface of the journal box.

Another object of the invention is to provide a rear oil seal of theabove type which fits easily and snugly into tight sealing engagementwithjournal box dust guard wells of varying width.

A further object of the invention is to provide a rear oil seal havingthe above advantages which is quite economical to manufacture in that itrequires a minimum amount of material and can be quitersimply formed.

Other objects and advantages of the invention will become apparent uponreading the following detailed description and upon reference to thedrawings in which:

FIGURE l is a longitudinal section of a conventional railroad journalbox assembly in which a rear oil seal constructed according to thepresent invention has been installed;

FIG. 2 is a transverse section taken along the line 2 2 in FIG. l; and

FIG. 3 is a section taken along the line 3 3 in FIG. 2.

While the invention will be described in connection with a preferredembodiment, it will be understood that I do not intend to limit theinvention to that embodiment. On the contrary, l intend to cover allalternatives, modilications and equivalents as may be included withinthe Mice spirit and scope of the invention as deiined by the appendedclaims.

Turning lirst to FIG. l, there is shown a railroad journal box 1liincluding a hinged front cover 12 and a circular aperture 13 formed iu adouble rear wall 14. Extending through the aperture 13 is an axle 15which includes a journal portion 16 and a iillet portion or dry seat 17.

y Resting on top of the journal 16 is the conventional supportingbearing structure or brass Ztl. It will be understood that the axlejournal 16 is free to revolve beneath the bearing 2@ and that thebearing, through the journal box 1li, transfers the weight of therailroad car to the axle l5.

For the purpose of conveniently mounting a rear oil seal in the rear ofthe journal box lil, the journal box rear wall llt is provided with adust guard well 22 generally of U-shaped outer configuration as can beseen in FIG. 2. The parts are so proportioned that the dry seat 1'7 ofthe axle 15 is disposed in the plane of the dust guard well 22 when theaxle and the journal box 10 are in their normal relative positions.

Providing a rotary seal enclosing the rear of the journal box 1t? is arear oil seal 3%embodying the present in vention, Vwhich is fullybottomed within the dustjguard well 22 and whichhas an annular sealingedge 3tlg snugly engaging the periphery of theaxle dry seat 17. The seal3@ is a unitary body formed lof resilient material having a continuousouter thickened portion or rim 31 shaped to t snugly within the well 22,an inner thickened portion or Vring 32 slightly distended about the axledry seat 17 so as to maintain a lirm sealing contact therewith, and arelatively thin web portion 33 joining the rim 31 and the ring 32 andforming a barrier closing and sealing the opening 13.

The seal 363 is not symmetrical when viewed in longitudinalsection, andtherefore the seal has a `wheel side 33a and a box side 33o facing,respectively, the wheel (not shown) on the axle 15 and the journal box1o@ Pursuant to the invention, the web portion 33 joins the rim. 31closelyadjacent the wheel` side 33a of the seal30 and the web is foldedonce at 3ft completely about its periphery toward the box side 33]) ofthe seal. The web 33 joins the ring 32. at the box side of the latter.

The effect of this arrangement is to dispose the ring 32 toward thewheel side 33a of the seal 33. The fold 34 provides llexibility betweenthe rim 31 and the ring 32 and allows free relative movement betweenthese parts in all directions but that direction in which the ring tendsto move toward the box side 33h of the seal. In other words, consideringthe rim 31 to be held steady, Vthe ring 32 can be easily moved up, downand tothe right in FIG. l, and from side to side in FIG. 2,` through theflexibility inthe fold 3ft. But movement of the ring 32 to the left inFIG. l can only be accomplished by stretching thematerialformingthe Web33. Thus, movement of the ring 32 toward the box side 33h ,of the sealis resisted by'thevseal construction.

The importance of providing flexibility between the ring 32 and the rim31 will be obvious to those skilled in the art. This liexibility allowsrelative movement between the axle and the journal box without damage tothe seal 3@ and without affecting its sealing effectiveness.

The importance of disposing the ring 32. toward the wheel side 33a ofthe seal 3% is that this minimizes the tendency of the ring to drop fromthe dry seat 17 since the edge 17a of the dry seat is as far away aspossible from the normal position of the ring 32. Thus, a maximum amountof axial relative movement between the journal box and the axle ispermitted before the ring 32 becomes unseated from the dry seat 17.

Although the ring 32 is kept ras far as possible from the edge 17a ofthe dry seat 17, experience has shown that relative movement between theaxle and the journal box is often suflicient to unseat the ring 32 fromthe dry seat. Such relative movement between the axle and the journalbox could occur, for example, when the railroad ear swings around arelatively sharp curve in the track so that the car, and hence thejournal box 1t?, slides to the left in 1li-G. l relative to the axle i5.lf this movement is sufricient, the ring 32 will -be carried over theedge 57a of the axle dry seat. Such extreme movement is always atemporary condition and the journal box llt?, after shifting to theleft, is usually slammed back to the right.

When the above described action occurs, it can be seen that tore-establish the normal position of the parts, the dry seat i7 must beforced within the ring 32, or more accurately, the ring 32 must beforced over onto the dry seat i7. Since the seal 3?' is constructed sothat movement of the ring 32 toward the box side of the seal is stronglyresisted by the seal itself, it can be seen that the ring 32 can bedrawn over the edge i715: and onto the dry seat 17 without jamming theweb 33 against the rough cast walis of the journal box. Stated anotherway, the seal 39 itself provides the required stiffness to permit thering 32 to move up onto the ry seat i7. Therefore, the web 33 is notjammed against the rough cast walls ot the journai box when the ring 32is forced onto the axle dry seat 17.

In accordance with a further aspect of the invention, the rim 3?. isformed with oppositely projecting ridges Il and 42 which are arrangedabout the lower portion of the rim to achieve snug sealing engagementwith the walls of the well 22, even though the Iwidth of the well 22.may vary through a very wide range. -It should be understood thatconventional railroad journal boxes such as the box l@ are formed bycasting and it is common experience to set permissible tolerances forthe width of the well 22 at as much as plus or minus /G of an inch. Therim 3d must thus be able to snugly' and easily tit within dust guardwells whose width might vary at least as much as 1/8 of an inch.

To achieve this result, the rim 3l is formed with a thickness that isless than the smallest well width likely to be encountered, the ridgesil and 42 are extracted suiciently tar so that the combined thickness ofthe rim 31 and the ridges 4i and 42 is greater than the widest guardwell likely to be encountered, and the ridges dll and 42 are laterallyoifset with respect to one another. The effect of this construction isbest shown in FXG. 3. When the rim 31 is pushed downwardlv into a dustguard well, the offset ridges are squeezed between the opposed walls ofthe well and act to twist the rim 31 by slightry distorting the wresilient material forming the rim. The fact that the rim 311 isiiexibly distorted as it is inserted into the well 22 permits the seal3l? to be moved into place without jamming. The slight twist of the rim31, dependent upon the thickness of the well 22, assures that the offsetridges 42 are urged into snug engagement with the opposite side walls ofthe well 22, even though the spacing of these walls may vary.

In order to stiften the outer shape of the seal 3o' and rig-idify therim 31, a steel reinforcement 45 is embedded within the rim 31. Tosiffen and rigidity the circular shape of the ring 32, a second steelreinforcement 46 is ernbedded within the material forming the ring 32.

It is contemplated that the seal 3d be molded as a single unt from asuitable oil resistant, resilient material, such as Buna-N, a syntheticrubber s-old under the trade name Hycaiz The molding operation requiredto form the seal Sti is relatively simple because of the uncomplicatedconliguration 4of the seal 30. Those skilled in the art will alsoappreciate that very little material is required to form the seal 3d andhence, for this further reason, the seal may be very inexpensivelymanufactured.

l claim as my invention:

l. As an article of manufacture, an oil seal comprising an integrallymolded unit of tlexible material including an outer thickened portionshaped to -iit within a journal box dust guard well, said outer' portionbeing thinner than the smallest allowable Width of a standard railroadjournal box dust guard well, an inner thickened portion circular inoutline for surrounding an axle dry seat in sealing engagement, arelatively' thin portion connecting said inner and outer portions, andintegral projecting sealing ridges extending one from each side of saidouter portion so that the overall thickness of the outer portion and itsridges is greater than the largest alowable width of a standard dustguard well, said ridges being laterally offset one from the other onsaid outer portion so that insertion of the unit into a dust guard wellcauses the outer portion to twist slightly to accommodate the width ofthef well with the sealing ridges snugly engaging the opposite wellwalls without jamming.

2. As an article of manufacture, an oil seal comprising an integrallymolded unit of resilient material including an outer thickened portionshaped to tit within a journal box dust guard well, an inner thickenedportion circular in outline for surrounding an axle dry seat in sealingengagement, a relatively thin portion connecting said inner and outerportions, said un-it having a wheel side and a box side to be disposed,when installed, facing the wheel and journal box respectively, said thinportion joining said outer portion closely adjacent the wheel side ofthe unit and being folded only once toward said box side completelyabout its periphery so as to dispose said inner portion at the wheelside of said unit, said single fold allowing free relative movementbetween said inner and outer portions in all directions but that inwhich the inner portion tends to move toward the box side of the unit,and integral projecting sealing ridges extending one from each side ofsaid outer portion so that the overall thickness of the outer portionand its ridges is greater than the largest allowable width of a standarddust guard well,l

said ridges being laterally oifset one from the `other on said outerportion so that insertion of the unit into a dust guard well causes theouter portion to twist slightly to accommodate the width of the wellwith the sealing ridges snugly engaging the opposite well walls withoutjamming.

References Cited in the file of this patent UNITED STATES PATENTS2,668,067 Fitzsimmons Feb. 2, 1954 2,692,783 Foss Oct. 26, 19542,758,853 Beck Aug. 14, 1956 2,872,219 Cobb Feb. 3, 1959

1. AS AN ARTICLE OF MANUFACTURE, AN OIL SEAL COMPRISING AN INTEGRALLYMOLDED UNIT OF FLEXIBLE MATERIAL INCLUDING AN OUTER THICKENED PORTIONSHAPED TO FIT WITHIN A JOURNAL BOX DUST GUARD WELL, SAID OUTER PORTIONBEING THINNER THAN THE SMALLEST ALLOWABLE WIDTH OF A STANDARD RAILROADJOURNAL BOX DUST GUARD WELL, AN INNER THICKENED PORTION CIRCULAR INOUTLINE FOR SURROUNDING AN AXLE DRY SEAT IN SEALING ENGAGEMENT, ARELATIVELY THIN PORTION CONNECTING SAID INNER AND OUTER PORTIONS, ANDINTEGRAL PROJECTING SEALING RIDGES EXTENDING ONE FROM EACH SIDE OF SAIDOUTER PORTION SO THAT THE OVERALL THICKNESS OF THE OUTER PORTION AND ITSRIDGES IS GREATER THAN THE LARGEST ALLOWABLE WIDTH OF A STANDARD DUSTGUARD WELL, SAID RIDGES BEING LATERALLY OFFSET ONE FROM THE OTHER ONSAID OUTER PORTION SO THAT INSERTION OF THE UNIT INTO A DUST GUARD WELLCAUSES THE OUTER PORTION TO TWIST SLIGHTLY TO ACCOMMODATE THE WIDTH OFTHE WELL WITH THE SEALING RIDGES SNUGLY ENGAGING THE OPPOSITE WELL WALLSWITHOUT JAMMING.